Effects of nasoalveolar molding on maxillary arch dimensions and malocclusion characteristics in primary dentition patients with cleft lip and palate.

BACKGROUND: Nasoalveolar molding (NAM) is a presurgical orthopedic technique used in the management of cleft lip and palate deformities. Despite the widespread use of NAM therapy, there is a need for further investigation to assess its specific effects on arch dimensions and malocclusion characteristics. AIM: To evaluate the effects of NAM therapy on maxillary arch dimensions and malocclusion characteristics in patients with unilateral cleft lip and palate (UCLP) and bilateral cleft lip and palate (BCLP). DESIGN: Patients in primary dentition were referred to the Institutional Department of Orthodontics. The NAM group consisted of 21 patients with UCLP (mean age 4.7 ± 0.7 years) and 12 patients with BCLP (mean age 4.8 ± 0.7 years). Sixteen patients with UCLP (mean age 4.9 ± 0.9 years) and five patients with BCLP (mean age 5.4 ± 1.1 years) were included in the non-NAM group. The plaster models of all patients were digitized. Dental arch dimensions and malocclusion characteristics were analyzed via digital software. One-way ANOVA with Bonferroni correction was used for statistical analysis. RESULTS: Intercanine and intermolar widths showed statistically significant differences according to the cleft type (p < .01). There was no statistically significant effect of NAM therapy on maxillary arch parameters and malocclusion characteristics (p > .05). The prevalence of anterior crossbite was 12.1% in the NAM group and 23.8% in the non-NAM group. CONCLUSION: NAM therapy did not affect the maxillary arch dimensions and malocclusion characteristics in patients with UCLP and BCLP. The cleft type was the main factor, leading to a significant difference in maxillary widths.

Is wear time of Hawley retainers measured with microsensors related to mandibular arch stability?

PURPOSE: The aim of this study was to show a possible correlation between the mean wear time of Hawley retainers and long-term mandibular arch stability as assessed via wear time analysis with microsensors. METHODS: This longitudinal retrospective study comprised 47 subjects (mean age 16.30 ± 1.06 years) having been treated with a nonextraction protocol and presenting moderate crowding at pretreatment. For retention, all patients were instructed to use a mandibular Hawley retainer for 12 months, and wear time was documented every 3 months during a posttreatment period of 6 months using TheraMon software. These individuals were divided into two groups. Those who adhered to a wear time equal to or more than 12 h/day (group 1A; N = 17) and those who complied for less than 12 h/day (group 2A; N = 30) were compared with respect to changes of the mandibular arch during the first 6 months of retention. Furthermore, a subgroup of 28 patients who completed a 12-month follow-up period were again divided into two groups: the individuals in group 1B (N = 12) adhered to a wear time equal to or more than 8 h/day, while those in group 2B (N = 16) complied for less than 8 h/day. Little's Irregularity Index, intercanine and intermolar widths, arch length, overjet, and overbite were measured on mandibular models taken at pretreatment (T0) and posttreatment (T1), as well as 6 months (T2) and 12 months (T3) after debonding. Pearson correlation test, independent samples t­test, and Mann-Whitney U test were used for statistical evaluation. RESULTS: From T1 to T2, group 1A and group 2A showed a significant relapse in intermolar width with a difference in the median value of 0.38 mm (p = 0.019). At the complete 12-month follow-up, the increase in Little's irregularity score was significantly greater in group 2B (2.54 ± 1.29 mm) than in group 1B (1.32 ± 1.03 mm; p = 0.012). The established wear time measurements showed significant negative correlations with the Little's irregularity score and overjet changes between T1 and T3 (p < 0.05). CONCLUSIONS: The results emphasized that the use of a retainer should not fall below a level of at least 8 h/day.

Relationship between vertical facial morphology and dental arch measurements in class II malocclusion: a retrospective study.

Background: To evaluate the relationship between dental arch measurements and the vertical facial pattern determined in skeletal Class II untreated patients. Methods: Lateral cephalograms and plaster models were obtained from 124 untreated female adults (average age: 17.6 ± 3.8 years). Class I (CI), Class II Division 1 (CII/1) and Class II Division 2 (CII/2) malocclusions were divided into three subgroups according to their vertical morphology as hypodivergent, normodivergent and hyperdivergent. The multivariate variance analysis (MANOVA) method was used in the comparison of measurement values according to vertical and sagittal morphology. The relationship between both A point-Nasion-B point (ANB) and Frankfurt-mandibular plane (FMA) angles and dental arch measurements was examined by Pearson correlation analysis. The significance level was received as p < 0.05. Results: While vertical morphology has a statistically significant effect on mandibular arch length, sagittal morphology affects maxillary arch depth. The parameters influenced by both morphologies are maxillary and mandibular arch length, as well as maxillary intermolar width. The mandibular arch length was significantly shorter in hyperdivergent-CII-2 malocclusion (50.5 ± 7.4 mm). Larger values were obtained in both mandibular arch length and maxillary arch depth measurements in CII-1 malocclusion compared to CII-2 malocclusion. The maxillary intermolar width was significantly shorter in hypodivergent-CII-1 malocclusion (46.8 ± 3.4 mm), while it was higher in hypodivergent-CI malocclusion (51.1 ± 3.4 mm). The maxillary arch length was the lowest in hyperdivergent-CI malocclusion (63.1 ± 13.3 mm) and the highest in hypodivergent-CI malocclusion (72.8 ± 7.6 mm). Additionally, a positive but weak correlation was found between ANB and FMA angles. Conclusion: Dental arch measurements have been found to be affected by both vertical facial morphology and skeletal sagittal relationship. A positive correlation was found between ANB and FMA angles.

Changes in Orbicularis Oris Superior and Masseter Muscle Activities After Upper Incisor Protrusion in Class II Division 2 Malocclusion: An Electromyographic Study.

OBJECTIVE: This prospective study aimed to evaluate the orbicularis oris superior and masseter muscle activity changes after upper incisor protrusion in CII/2 malocclusion. METHODS: A total of 20 patients (mean age 10.29 ± 0.90 years) with CII/2 malocclusion were selected for the study group. A total of 15 patients (mean age 10.56 ± 1.06 years) with Angle Class I malocclusion were recruited as control. Upper incisors were protruded with utility arch in the study group. Muscle activities were evaluated with Biopac MP150 surface electromyography device before and after upper incisor proclination and at the 6-month retention. Orbicularis oris superior and left-right masseter muscles were recorded during rest electromyography and maximum contraction electromyography. Repeated measures and two-way repeated-measures analysis of variance with Bonferroni correction were used for statistical analysis. RESULTS: A significant change occurred over time in orbicularis oris superior (P < 0.001), left masseter (P < 0.01) and right masseter (P < 0.05) maximum contraction electromyography in the CII/2 group. However, a significant difference was not found between groups P > 0.05. In the CII/2 group, orbicularis oris superior maximum contraction electromyography value was increased after upper incisor protrusion and this increase remained stable. Left masseter and right masseter maximum contraction electromyography measurements were decreased after protrusion and then increased after retention significantly. Rest electromyography values for all muscles were not statistically significant. No significant differences with the control group were found. CONCLUSION: Upper incisor protrusion increased orbicularis oris superior activity and the increase remained stable after retention. Masseter activities decreased after protrusion and then increased to the initial values. These changes did not show significant differences with the control group.

Vertical Facial Skeletal Asymmetry and Occlusal Cant Relationship in Patients With Unilateral Cleft Lip and Palate.

OBJECTIVE: To evaluate the maxillary and mandibular vertical skeletal asymmetries, and the correlation between these asymmetries and occlusal cant in patients with unilateral cleft lip-palate (UCLP). METHODS: Anteroposterior radiographs of 25 patients with UCLP (UCLP group, mean age: 20.98 ± 4.88 years) and 25 subjects without cleft (control group, mean age: 19 ± 2.86 years) were included. Independent samples t test, Mann-Whitney U test and Pearson correlation analysis were performed based on linear and angular measurements. RESULTS: Lower facial horizontal asymmetry did not show statistically significant difference between the UCLP and control groups. However, vertical asymmetry of (a) the lateral cranial base (P = .014), (b) the nasomaxillary region (P < .001), (c) the maxillary dentoalveolus (P = .001), and (d) the lower face (P = .038) were all found to be significantly greater in UCLP group. The occlusal cant angle was also significantly greater in patients with UCLP compared to the controls (P = .016). While the occlusal cant angle was found to be correlated with the vertical asymmetry of the occlusal cant (r = 0.931, P < .001), maxillary cant angle was found to be correlated with the vertical asymmetry of the maxillary dentoalveolus (r = 0.655, P < .001). CONCLUSIONS: There was no correlation between the occlusal cant and the vertical and horizontal skeletal asymmetries. Vertical asymmetries of the lower face and the medial cranial base were negatively correlated with the horizontal lower facial asymmetry.

Comparison of Transverse Craniofacial Dimensions Between Growing Individuals With Unilateral Cleft Lip and Palate and Age-and Sex-Matched Noncleft Controls.

OBJECTIVE: The study aimed to assess the transverse craniofacial dimensions of patients (age, 7-14 years) with unilateral cleft lip and palate (UCLP), compare these dimensions with those of noncleft individuals, and identify the correlations between the nasal and maxillary transverse widths of patients with UCLP. DESIGN: A cross-sectional study. PARTICIPANTS: Eighty patients operated on for complete UCLP (UCLP group; 35 girls, 45 boys; median age: 10.7 [7.9-14] years) and 80 age- and sex-matched noncleft individuals (control group; 35 girls, 45 boys; median age: 10.7 [7.3-14] years). INTERVENTIONS: Interorbital, bizygomatic, nasal, maxillary skeletal, maxillary molar, mandibular molar, and antegonial width measurements were performed using posteroanterior cephalometric radiographs. Intergroup comparisons were conducted by using the independent samples t-test and Mann-Whitney U test. Correlation between the variables was examined using Pearson correlation analysis. RESULTS: The bizygomatic, maxillary skeletal and molar, mandibular molar, and antegonial widths in the UCLP group were significantly less than those in the control group (P < .05). A positive correlation was found between the maxillary skeletal and nasal widths (r = 0.550, P < .001) and between the maxillary molar and nasal widths (r = 0.560, P < .001). CONCLUSIONS: In individuals with UCLP, the bizygomatic, maxillary skeletal and molar, mandibular molar, and antegonial widths were significantly less than those in noncleft individuals. As the maxillary skeletal and dental widths presented a positive correlation with the nasal width, a decrease in nasal width must be considered when maxillary constriction is noted.

Comparison of Positive Screening for Obstructive Sleep Apnea in Patients With and Without Cleft Lip and Palate.

OBJECTIVE: To compare the prevalence of increased risk of obstructive sleep apnea (OSA) in children with and without cleft lip and/or palate using a previously validated questionnaire and to examine the clinical and demographic variables that may lead to increased OSA risk. DESIGN: Prospective, cross-sectional study. PARTICIPANTS: One hundred fifty-five cleft lip palate and 155 noncleft children between 2 and 18 years old. INTERVENTIONS: The Pediatric Sleep Questionnaire (PSQ): Sleep Related Breathing Disorder Scale was used for screening of increased OSA risk. Age, body mass index (BMI), gender, breast-feeding, and bottle-feeding durations were recorded for all patients. Cleft type, lip and palate operation times, nasoalveolar molding, or nutrition plaque usage was documented for the cleft lip palate group. Pearson χ2 or Fisher exact test was used for the evaluation of the qualitative variables and independent samples t test or Mann Whitney U test for quantitative variables. P < .05 was accepted as statistically significant. RESULTS: The mean ages were 7.52 ± 3.91 and 7.50 ± 3.89 years for cleft lip palate and control groups, respectively. No significant differences were observed between the groups for age, gender, or BMI. Breast-feeding duration was significantly higher, and bottle-feeding duration was lower in the control group (P < .05). Mean PSQ score was significantly higher in cleft lip palate group (0.18 ± 0.12) than in control group (0.13 ± 0.1, P < .001); and prevalence of increased OSA risk was significantly higher in patients with both cleft lip and palate (P = .020). CONCLUSIONS: Positive OSA screening ratio of children with cleft lip and palate (12.2%) was significantly higher than the controls (4.5%).

Upper airway features of unilateral cleft lip and palate patients in different growth stages.

OBJECTIVES: To compare growth-related changes of skeletal and upper airway features of unilateral cleft lip and palate subjects (UCLP) with non-cleft control (NCC) subjects by using lateral cephalograms. MATERIALS AND METHODS: The sample comprised 238 subjects, collected cross-sectionally, divided into 2 groups: 94 with UCLP, and 144 NCC, subdivided into 4 groups according to their growth stages by using cervical vertebral maturation stage (CVMS). The subgroups were defined as early childhood (stage 1), prepubertal (stage 2: CVMS I and II), pubertal (stage 3: CVMS III and IV), and postpubertal (stage 4: CVMS V and VI). RESULTS: The maxilla was more retrognathic at stages 2, 3, and 4 in females with UCLP. The mandible was more retrognathic in UCLP at stage 1 in males, and stages 2 and 3 in females. ANB (angle between NA plane and NB plane) was significantly smaller in UCLP subjects at stage 4 for both sexes. A vertical growth pattern was seen in UCLP subjects except males at stages 2 and 3, and females at stage 2. Posterior airway space was significantly narrower at all stages in males and after stage 1 in females. Middle airway space was significantly wider at all stages in females and after stage 1 in males. Epiglottic airway space was significantly narrower in males at stage 3. CONCLUSIONS: Age- and sex-dependent differences in skeletal morphology and upper-airway widths of the UCLP subjects were identified when compared with controls.

Influence of nasoalveolar molding on skeletal development in patients with unilateral cleft lip and palate at 5 years of age.

INTRODUCTION: The aim of this retrospective study was to assess the influence of presurgical nasoalveolar molding (NAM) on skeletal development in patients with operated unilateral cleft lip and palate at 5 years of age. MATERIALS: Lateral cephalometric radiographs of 26 unilateral cleft lip and palate patients who had undergone presurgical NAM (NAM group) and 20 unilateral cleft lip and palate patients who did not have any presurgical NAM (non-NAM group) were analyzed. The radiographs were digitally traced using Quick Ceph Studio software (version 3.5.1.r (1151); Quick Ceph Systems, San Diego, Calif). Independent samples t tests were performed for statistical analysis. RESULTS: No significant differences were observed in sagittal and vertical skeletal measurements between the NAM and non-NAM groups. CONCLUSIONS: NAM resulted in no significant difference in skeletal development in unilateral cleft lip and palate patients compared with those without NAM in early childhood.

Assessment of upper airway size after orthopedic treatment for maxillary protrusion or mandibular retrusion.

INTRODUCTION: The aim of this retrospective study was to find out whether different Class II treatments would affect the airway sizes of patients having maxillary protrusion or mandibular retrusion. METHODS: The study sample comprised 57 Class II patients whose upper airway sizes were not significantly different at the start of treatment and whose sagittal skeletal jaw relationships showed that they had maxillary protrusion or mandibular retrusion. Twenty-two of them were treated with cervical headgear, 16 with activator, and 19 were selected as a control. Lateral cephalograms at the start of treatment and the end of orthopedic treatment were assessed. The intragroup comparisons were performed by using the paired-samples t test, and intergroup comparisons of the skeletal features and upper airways were performed with 1-way analysis of variance, with the Tukey test as a second step, at P < 0.05. RESULTS: The ANB angle decreased significantly in the treatment groups. The middle airway space and the SNB angle were significantly increased after the activator therapy (P < 0.05). The SNB angle increased and SN-1 decreased in the mandibular retrusion group when compared with both maxillary protrusion and control groups. No statistically significant difference between the maxillary protrusion and the mandibular retrusion groups was found regarding the upper airway sizes after cervical headgear or activator treatments, respectively (P > 0.05). The only significant differences observed in airway variables were at the middle airway space of the activator and control groups with an increase of 1.6 ± 2.5 mm and a decrease of 1.5 ± 2.3 mm, respectively. CONCLUSIONS: Orthopedic treatment with either cervical headgear or activator did not result in different upper airway changes, but activator treatment resulted in increased middle airway space with regard to the Class II control group.

Changes in lips, cheeks and tongue pressures after upper incisor protrusion in Class II division 2 malocclusion: a prospective study.

BACKGROUND: The etiology of Class II division 2 (CII/2) malocclusion focuses on heredity; however lip, cheek, and tongue pressures that are associated with the environmental effect are considered to have an effect. The aim of this study was to evaluate the relation between perioral pressures and the upper incisor inclination in CII/2 malocclusion. METHODS: Twenty patients (8 females, 12 males; mean age 10.29 ± 0.90 years) with CII/2 malocclusion were included in the study group, and 15 patients (5 females, 10 males; mean age 10.56 ± 1.06 years) with Class I malocclusion were included. The upper incisors were protruded with a utility arch (0.016 × 0.022 in. blue elgiloy wire). Perioral pressure assessment was made with the Iowa Oral Pressure Instrument. Upper lip pressure, lower lip pressure, vertical lip pressure, left-right buccal pressures, swallowing, and maximum tongue pressures were measured. Repeated measure ANOVA was used to test the intragroup differences. Intergroup comparisons were made using two-way repeated measure ANOVA with Bonferroni correction. Relationships between the variables were analyzed using rank correlation (Spearman's rho). The significance for all statistical tests was predetermined at p < 0.05. RESULTS: A significant change occurred in the upper lip pressure, lower lip pressure, and vertical lip pressure; however, significant difference was not found between the groups. Upper lip pressure increased significantly in both groups. In the CII/2 group, lower lip pressure increased after protrusion and decreased after retention, while vertical lip pressure decreased and then increased significantly. Left buccal pressure changes between the groups were not parallel. Right buccal pressure, swallowing, and maximum tongue pressure changes were not statistically significant. Statistically significant correlation was found between U1-NA (mm) and vertical lip pressure (r -0.467). CONCLUSIONS: In the CII/2 group, upper lip pressure increased only in retention. Lower lip pressure increased and vertical lip pressure decreased after protrusion. Nevertheless, these changes did not remain stable after the retention period. The difference between groups was not statistically significant at the end of retention.

Growth-related changes of skeletal and upper-airway features in bilateral cleft lip and palate patients.

INTRODUCTION: The craniofacial morphology of subjects with cleft lip and palate differs from that of subjects without clefts. Subjects with bilateral cleft lip and palate tend to have maxillary retrognathism, a smaller mandible with an obtuse gonial angle, greater anterior upper and lower facial heights, and retroclined maxillary incisors. The purposes of this research were to compare the skeletal and upper-airway features of subjects with bilateral cleft lip and palate with the same features in control subjects without clefts and to determine the growth-related changes at different growth stages. METHODS: The sample comprised 212 subjects divided into 2 groups: 68 with bilateral cleft lip and palate, and 144 controls without clefts; each group was further divided into 4 subgroups according to growth stage using the cervical vertebral maturation stage method. The subgroups were defined as early childhood (stage 1), prepubertal (stage 2), pubertal (stage 3), and postpubertal (stage 4). The cephalometric variables were evaluated with 2-way analysis of variance and the Bonferroni test. RESULTS: Maxillary position showed no significant differences between the male groups. The maxilla was more prognathic at stage 2 and became more retrognathic at stages 3 and 4 in the females. The mandible was more retrusive in the bilateral cleft lip and palate subjects at stage 1 in males and at stages 3 and 4 in females. ANB was larger at stages 1 and 2, and it became similar to the controls at stages 3 and 4 in male and female bilateral cleft lip and palate subjects. Vertical growth was seen in the bilateral cleft lip and palate subjects regardless of sex, and no change was observed with age. Posterior airway space was narrower in all stages (except for stage 1 in females). Middle airway space was wider after stage 1 in the male and female bilateral cleft lip and palate subjects. Inferior airway space was narrower in the male bilateral cleft lip and palate patients at the early childhood and pubertal stages. CONCLUSIONS: Age- and sex-dependent differences in skeletal morphology and upper-airway widths of the bilateral cleft lip and palate subjects were identified when compared with the control subjects without clefts.

Influence of two different bracket base cleaning procedures on shear bond strength reliability.

PURPOSE: To search if the shear bond strengths of brackets would change after two different base-cleaning procedures such as sandblasting or carbide bur cleaning, and to determine if a previously bonded tooth surface had any effect on bond strength. MATERIALS AND METHODS: A total of 120 new brackets were first bonded to 120 extracted premolars and then debonded and bond strength was recorded. The debonded brackets were divided into two groups and recycled either by sandblasting or tungsten-carbide bur cleaning. Sixty recycled brackets were divided into two subgroups: In each group; 30 recycled brackets were bonded to unused 30 extracted premolars. The remaining brackets were bonded to 30 previously used premolars. The brackets were debonded again and their bond strengths were remeasured. RESULTS: Bond strength of rebonded brackets after sandblasting was not significantly different from that of new brackets while the bond strength of rebonded brackets after carbide bur cleaning group significantly decreased. The previously bonded tooth surface did not affect the bond strength significantly. CLINICAL SIGNIFICANCE: This study showed that rebonding the brackets after sandblasting supplies sufficient bond strength. Previously bonded tooth surface did not cause a decreasing effect on bond strength. However, when carbide bur cleaning procedure is chosen, the clinician should proceed cautiously.

IgG-based elimination diet in migraine plus irritable bowel syndrome.

OBJECTIVES: To evaluate therapeutic potential of the immunoglobulin G (IgG)-based elimination diet among migraine patients with irritable bowel syndrome (IBS). BACKGROUND: Food elimination has been suggested as an effective and inexpensive therapeutic strategy in patients with migraine and concomitant IBS in the past studies. METHODS: A total of 21 patients (mean [standard deviation] age: 38.0 [11.2] years; 85.7% females) diagnosed with migraine and IBS were included in this double-blind, randomized, controlled, cross-over clinical trial composed of baseline (usual diet), first diet (elimination or provocation diets), and second diet (interchange of elimination or provocations diets) phases and 4 visits. RESULTS: IgG antibody tests against 270 food allergens revealed mean (standard deviation) reaction count to be 23.1 (14.1). Compared with baseline levels, elimination diet per se was associated with significant reductions in attack count (4.8 [2.1] vs 2.7 [2.0]; P < .001), maximum attack duration (2.6 [0.6] vs. 1.4 [1.1] days; P < .001), mean attack duration (1.8 [0.5] vs. 1.1 [0.8] days; P < .01), maximum attack severity (visual analog scale 8.5 [1.4] vs. visual analog scale 6.6 [3.3]; P < .001), and number of attacks with acute medication (4.0 [1.5] vs. 1.9 [1.8]; P < .001). There was a significant reduction in pain-bloating severity (1.8 [1.3] vs. 3.2 [0.8]; P < .05), pain-bloating within the last 10 days (3.2 [2.8] vs. 5.5 [3.1]; P < .05), and improvement obtained in quality of life (3.6 [1.4] vs. 2.9 [1.0]; P < .05) by the elimination diet as compared with provocation diet. CONCLUSIONS: Our findings indicate that food elimination based on IgG antibodies in migraine patients who suffer from concomitant IBS may effectively reduce symptoms from both disorders with possible positive impact on the quality of life of the patients as well as potential savings to the health-care system.

Pharyngeal airway changes associated with maxillary distraction osteogenesis in adult cleft lip and palate patients.

PURPOSE: To investigate 1) the changes in pharyngeal airway sizes associated with maxillary distraction osteogenesis and 2) the correlations between maxillary skeletal variables and the pharyngeal airway in adult patients with cleft lip and palate. PATIENTS AND METHODS: The study was carried out in 14 adult subjects with cleft lip and palate. Predistraction records were taken at a mean age of 22.7 ± 4.6 years. All patients had placement of a rigid external distraction device (RED I; KLS Martin, Tuttlingen, Germany) after Le Fort I osteotomy. Lateral cephalograms were assessed before surgery and at short-term follow-up (8.0 ± 6.4 months). The cephalometric skeletal and pharyngeal airway variables were statistically evaluated by use of the Wilcoxon signed-rank test. Spearman ρ correlation was performed to check the correlations between maxillary skeletal and pharyngeal variables. RESULTS: The maxillary movement was 8.7 mm (P < .01). The maxillary depth angle (+7.9°) and effective maxillary length (9.4 mm) increased significantly (P < .01) after distraction, whereas the palatal plane angle remained unchanged. Anterior nasal spine (8.2 mm) and Posterior nasal spine (6.9 mm) moved anteriorly. The overjet increased (9.5 mm) significantly (P < .01). Posterior, superoposterior, and middle airway spaces increased significantly, with mean differences of 7.5 mm, 5.1 mm, and 3.3 mm, respectively. The soft palate moved anteriorly, with the greatest movement at its superior point. Significant positive correlations were observed for the posterior and superoposterior airway spaces and maxillary movement. PNS changes showed the highest correlation with posterior airway changes. CONCLUSIONS: The significant anterior movement of the maxilla resulted in significant increases in posterior, superoposterior, and middle airway spaces. The posterior airway space showed the highest significant positive correlation with the movement of PNS. The posterior and superoposterior airway spaces also showed significant positive correlations with the maxillary skeletal variables.

A prospective clinical evaluation of mandibular lingual retainer survival.

Bonded retainers are considered reliable, independent of patient co-operation, and highly efficient. However, most studies regarding the survival of retainers are retrospective. The aims of this investigation were to prospectively evaluate the failure rate of bonded lingual retainers, the influence of direct or indirect bonding procedures on survival, and to determine the distribution of failures over a 6 month period. Mandibular lingual retainers were bonded in 66 patients. Thirty-two retainers were bonded using a direct method and 34 by an indirect method. There were 23 females and 9 males (mean age 15.96 ± 3.21 years) in the direct group and 29 females and 5 males (mean age 19.44 ± 6.79 years) in the indirect group. A 0.016 × 0.022 inch Bond-a-Braid retainer wire (eight-braided, flattened, stainless steel dead soft wire) was used with Transbond LR. Following bonding, the patients were observed monthly. A chi-square test was used to analyse the influence of the direct and indirect procedures on survival rate.Twenty-five retainers failed. The failure rate was 46.9 per cent with the direct method and 29.4 per cent with the indirect method. The difference between the methods was not statistically significant. The total failure rate was 37.9 per cent. The highest failure rate was seen in the first month. Seven patients had repeated failures. The failure rate was higher in the right quadrant. The total survival rate was 62.1 per cent.

Reliability of reference distances used in photogrammetry.

OBJECTIVE: To determine the reliability of the reference distances used for photogrammetric assessment. MATERIALS AND METHODS: The sample consisted of 100 subjects with mean ages of 22.97 +/- 2.98 years. Five lateral and four frontal parameters were measured directly on the subjects' faces. For photogrammetric assessment, two reference distances for the profile view and three reference distances for the frontal view were established. Standardized photographs were taken and all the parameters that had been measured directly on the face were measured on the photographs. The reliability of the reference distances was checked by comparing direct and indirect values of the parameters obtained from the subjects' faces and photographs. Repeated measure analysis of variance (ANOVA) and Bland-Altman analyses were used for statistical assessment. RESULTS: For profile measurements, the indirect values measured were statistically different from the direct values except for Sn-Sto in male subjects and Prn-Sn and Sn-Sto in female subjects. The indirect values of Prn-Sn and Sn-Sto were reliable in both sexes. The poorest results were obtained in the indirect values of the N-Sn parameter for female subjects and the Sn-Me parameter for male subjects according to the Sa-Sba reference distance. For frontal measurements, the indirect values were statistically different from the direct values in both sexes except for one in male subjects. The indirect values measured were not statistically different from the direct values for Go-Go. The indirect values of Ch-Ch were reliable in male subjects. The poorest results were obtained according to the P-P reference distance. CONCLUSIONS: For profile assessment, the T-Ex reference distance was reliable for Prn-Sn and Sn-Sto in both sexes. For frontal assessment, Ex-Ex and En-En reference distances were reliable for Ch-Ch in male subjects.

Skeletal and dental stability after maxillary distraction with a rigid external device in adult cleft lip and palate patients.

PURPOSE: To evaluate skeletal and dental stability in adult cleft lip and palate patients treated with a rigid external distraction system at the end of distraction and during the postdistraction period. PATIENTS AND METHODS: Lateral cephalograms of 7 patients were obtained before distraction, at the end of distraction, and during the postdistraction period. The mean age before distraction was 21.56 +/- 4.73 years. The mean follow-up was 37.3 +/- 12.4 months. RESULTS: The assessment of findings showed that skeletal maxillary sagittal movement was achieved in a superoanterior direction. The maxillary depth angle and effective maxillary length increased significantly (2 degrees and 9 mm, respectively) after distraction, whereas the palatal plane angle increased by 8 degrees , resulting in an anterior movement of the maxilla with a counterclockwise rotation. The lower facial height showed no significant changes after distraction. The sagittal movement of the upper incisors and the angulation of the upper first molars increased significantly (4.5 mm and 5.5 degrees , respectively). During the postdistraction period, the maxilla showed a slight relapse (22%). The effective maxillary length decreased by 2 mm. The palatal plane angle almost returned to its original position, showing 7 degrees of clockwise rotation. The lower facial height remained stable. The upper incisors moved anteriorly and the upper first molars showed a significant mesioangular change during follow-up. CONCLUSIONS: After distraction, significant maxillary advancement was achieved with a counterclockwise rotation. The upper incisors moved labially, and the upper first molars angulated mesially. After 3 years, a 22% relapse rate was seen in the maxilla. The counterclockwise rotation of the maxilla was returned to its original position. The upper incisors moved more anteriorly.

Botulinum toxin in closed treatment of mandibular condylar fracture.

BACKGROUND: The topic of condylar injury in adults has generated more discussion and controversy than any other in the field of maxillofacial trauma. The treatment of condylar fractures in adults is still a highly debated theme. METHODS: Patients with unilateral subcondylar or condylar neck fractures of the mandibula without any significant angulation of the condylar head were managed with closed-treatment protocol. Closed treatment was applied through the injection of 100 units of botulinum toxin A, diluted to a concentration of 20 IU/mL, into the muscles of mastication of the fractured side. Masseter and anterior fibers of temporalis muscles were reached through percutaneous extraoral route and 30 IU of the toxin was injected to each muscle. Additional 40 IU of the toxin was injected around the fractured bone fragments through transmucosal intraoral route to paralyze medial and lateral pterygoid muscles as much as possible. An asymmetric occlusal splint was applied for maxillomandibular fixation to restore the vertical height for 10 days. Functional therapy with intermaxillary guiding elastics was advocated for 2 months. RESULTS: There were no complications related to either toxin injections or splint application procedures. The toxin was effective on all occasions. Fractured condylar process and ramus of the mandibula were in good approximation and remained in reduced positions. None of the patients had any occlusal disturbance, mandibular asymmetry, or joint dysfunction in the follow-up period. CONCLUSIONS: We believe that modification of treatment options concerning the clinical situation of the patients is the best method for condylar injury. The purpose of this study is to present and discuss the results achieved in closed treatment of a selected group of patients with mandibular condylar fractures to whom botulinum toxin A was injected to relieve the spasm of muscles of mastication, along with special splint application.